How do you add decimals in BCD?
BCD addition of given Decimal numbers
- Input: A = 12, B = 20.
- Output: 110010.
- Explanation: The summation of A and B is 12 + 20 = 32. The binary representation of 3 = 0011. The binary representation of 2 = 0010. Therefore, the BCD Addition is “0011” + “0010” = “110010”
What are different rules for BCD addition?
But the result of addition in case 2 is less than 9, which is valid for BCD numbers. If the four bit result of addition is greater than 9 and if a carry bit is present in the result then it is invalid and we have to add 6 whose binary equivalent is (0110)2 to the result of addition.
Is BCD a weighted code?
In other words, the BCD is a weighted code and the weights used in binary coded decimal code are 8, 4, 2, 1, commonly called the 8421 code as it forms the 4-bit binary representation of the relevant decimal digit.
Why do we add 6 in BCD?
When you do math in decimal, if a number is larger than 10 you need to take the modulus of 10 and carry to the next row. Similarly, in BCD math, when the result of the addition is larger than 9 you add 6 to skip the 6 remaining “invalid” values and carry to the next digit.
Why do we add 6 in BCD addition?
What is valid BCD number?
Binary Coded Decimal (BCD) code BCD is a way to express each of the decimal digits with a binary code. In the BCD, with four bits we can represent sixteen numbers (0000 to 1111). But in BCD code only first ten of these are used (0000 to 1001). The remaining six code combinations i.e. 1010 to 1111 are invalid in BCD.
Why BCD is used?
BCD was commonly used for displaying alpha-numeric in the past but in modern-day BCD is still used with real-time clocks or RTC chips to keep track of wall-clock time and it’s becoming more common for embedded microprocessors to include an RTC. It’s very common for RTCs to store the time in BCD format.